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M72 LAW
The M72 LAW (Light Anti-Tank Weapon, also referred to as the Light Anti-Armor Weapon or LAW as well as LAWS Light Anti-Armor Weapons System) is a portable one-shot 66 mm unguided anti-tank weapon, designed in the United States by Paul V. Choate, Charles B. Weeks, and Frank A. Spinale et al. while with the Hesse-Eastern Division of Norris Thermadore, currently produced by Nammo Raufoss AS in Norway. In early 1963 the LAW was adopted by the United States Army and United States Marines as their primary individual infantry anti-tank weapon, replacing the M31 HEAT rifle grenade and the M20A1 "Super Bazooka" in the US Army. It was subsequently adopted by the United States Air Force to serve in an anti-emplacement/anti-armor role in Air Base Defense duties.Mary T. Cagle "History of the TOW Missile System" page 10, US Army 1977 Redstone Arsenal Pdf file of official TOW history that discussed the new family of antitank weapons, the M72 LAW, the Dragon and the TOWThe US Army partially replaced the Super Bazooka not only with the M72 LAW, but also M67 recoilless rifle and US Marines kept the Super Bazooka in service till the late 1960s It had been intended that in the early 1980s that the M72 would be replaced by the FGR-17 Viper, but this program was canceled by Congress and the M136 AT4 was introduced in its place. In that time period its nearest comparison was the Swedish Pskott m/68 (Miniman) and the French was never adopted by the French Army - export only History During World War II, the sudden prominence of tanks and other armored vehicles on the battlefield led to the creation of man-portable weapons that would enable the humble infantryman to successfully deal with the new threat. The first such weapons to be used with limited success were [[flamethrower]s, satchel charges, jury-rigged landmines and specially designed magnetic hollow charges, but all these weapons needed to get within a couple of meters from the target to be effective, which severely limited said effectiveness and greatly endangered the user. The U.S. Army then introduced the bazooka on the battlefield, the first true rocket-propelled grenade launcher, which proved an effective novel weapon against enemy armor. Despite early problems, it was such a success that many involved nations during World War II soon copied or developed weapon systems in concept like the bazooka for extensive use on all fronts. However, the bazooka had its drawbacks. Being large, cumbersome and rather fragile, it needed a dedicated and trained two-man team to be used efficiently. Hard-pressed on all fronts, Germany developed one man alternative to the bazooka type weapons: the Panzerfaust family of weapons. These one-shot launchers were relatively cheap to manufacture and needed no specialized training; they were so simple to use that they were regularly issued to Volkssturm regiments. They proved remarkably efficient against any tanks they were used against during World War II. Noticeably, they were not rocket launchers but recoilless rifles. The M72 LAW is a descendant and combination of the two World War weapons; the basic principle is that of a miniaturized bazooka, while its low weight and cheap build allows for general issue and disposability akin to the Panzerfaust. Description The weapon consists of a rocket packed inside of a launcher made up of two tubes, one inside the other. While closed, the outer assembly acts as a watertight container for the rocket and the percussion cap-type firing mechanism that activates the rocket. The outer tube contains the trigger, the arming handle, front and rear sights, and the rear cover. The inner tube contains the channel assembly which houses the firing pin assembly, including the detent lever. When extended, the inner tube telescopes outward toward the rear, guided by the channel assembly which rides in an alignment slot in the outer tube's trigger housing assembly. This causes the detent lever to move under the trigger assembly in the outer tube, both locking the inner tube in the extended position and cocking the weapon. Once armed, the weapon is no longer watertight even if the launcher is collapsed into its original configuration. When fired, the striker in the rear tube impacts a primer which ignites a small amount of powder that "flashes" down a tube to the rear of the rocket igniting the propellant in the rocket motor, The rocket motor burns complete before leaving the mouth of the launcher, producing gases around 1,400 °F (760 °C). The rocket propels the 66 mm warhead forward without significant recoil. As the warhead emerges from the launcher, six fins spring out from the base of the rocket tube, stabilizing the warhead's flight.note - no matter what you see in the movies, training films show, there is no "Whoosh!" on launch -- ie more of a loud "BANG!!" or a "BLOOP!" for the training versions -- and there is no smoke trail behind the rocket as it heads towards the target The early LAW warhead, developed from the M31 HEAT rifle grenade warhead, uses a simple, but extremely safe and reliable piezoelectric fuze system, which on impact with the target a certain type of crystal in the front nose section is crushed causing a micro-second electric current to be generated which detonates the warhead. The fuse then detonates a booster charge located in the base of the warhead which sets off the main warhead charge. The force of the main charge forces the copper liner into a directional particle jet that in relation to the size of the warhead is capable of massive amount of penetration. A unique mechanical set-back safety on the base of the detonator grounds the circuit till the missile is accelerated from the tube. The accelerations causes each of the three disks in the set back to rotate 90 degrees in succession, ungrounding the circuit and completing a circuit from the nose to the base of the detonator when the piezo-electric crystal is crushed on impact. Ammunition slung over the soldier's back.]] The M72A2 LAW was issued as a prepackaged round of ammunition. Improvements to the launcher and differences in the ammunition were differentiated by a single designation. The most common M72A2 LAWs came prepacked with a rocket containing a 66 mm HEAT warhead which is attached to the inside of the launcher by the igniter. The standard M72A2 anti-armor HEAT warhead has an official stated penetration in 1977 of up to 20 cm/8 inches of steel plate, 600mm (2 feet) of reinforced concrete, or 1.8 meters (6 feet) of soil.US Army publication September 30, 1977 "FM-7 The Mechanized Infantry Platoon/Squad Section B-21"Note - before the publication of FM-7 September 1977, various penetration specifications were given for the M72A2 and the M31 HEAT. Anywhere from 250mm to 305mm. In the mid 1970s the US Army decided to determine the armor penetration under battlefield conditions again Soviet-made tanks captured in 1973. The result was 20cm/8 inches the proceeding penetration specification is stated as it appears in FM-7 1977. A training variant of the M72 LAW, designated the M190, also exists. This weapon is reloadable and uses the 35 mm M73 training rocket. A subcaliber training device that uses a special tracer cartridge also exists for the M72. A training variant used by the Finnish armed forces fires 7.62 mm tracer rounds. The US Army tested other 66 mm rockets based on the M54 rocket motor used for the M72. The M74 TPA (Thickened Pyrophoric Agent) had an Incendiary warhead filled with TEA (triethylaluminium); this was used in the M202A1 FLASH (FLame Assault SHoulder weapon) 4-tube launcher. The XM96 RCR (Riot Control Rocket) had a CS gas-filled warhead for crowd control and was used with the XM191 quadruple-tube launcher. Once fired in combat the launcher is required to be destroyed to prevent its use by the enemy. Due to the single use nature of the weapon, it was issued as what is called a "wooden-round" of ammunition by the Canadian Army and the United States Army, requiring no checks or maintenance, just as small arms ammunition can be stored in the same manner for years without any problems. Service history Republic of China The Republic of China Army (Taiwan) uses the M72 as a secondary anti-armor weapon. It is used primarily as a backup to the Javelin and the M136 (AT4) anti-tank weapons. United States During the Vietnam and post-Vietnam periods, all issued LAWs were recalled due to instances of the warhead exploding in flight, sometimes injuring the operator. After safety improvements, part of the training and firing drills included the requirement to ensure the words "w/coupler" were included in the text description stenciled on the launcher, which indicated the launcher had the required safety modification(s).some reports state it was over water in the flash tube causing dangerous misfires and unproven rumors of possible sabotage at the manufacturing plant during the Vietnam War With the failure of the M72 replacement the Viper, Congress in late 1982 ordered the US Army to test off-the-shelf light antitank weapons and report back by the end of 1983. In partnership with Raufoss AS, Talley Defense offered the M72E5, which offered increased range, penetration and better sights, which was tested along with five other light anti-armor weapons in 1983. For all the improvements the M72E5 offered the AT4 was chosen to replace the M72.D. Kyle, Armed Forces Journal International/November 1983 "Viper Dead, Army Picks AT-4 Antitank Missile" page 21Various reports in 1983 stated that during the Congressional mandated tests the first M72E5 tested had an accuracy problem, because of its larger-diameter rocket motor, interfered with the deployment of all the stabilizing fins after leaving the launcher. The manufactures have since made modifications that have worked that problem out. Although generally thought of as a Vietnam War era weapon which has been superseded by more powerful AT4, the M72 LAW has found a new lease of life in the ongoing (2006) operations in Iraq by the US Army and Afghanistan by the US Marine Corps and Canadian Army. Variants US variants Specifications (M72A2 and M72A3) Launcher *'Length': **Extended: less than 1 m (35 in). **Closed: 0.67 m (24.8 in). *'Weight': **Complete M72A2: 2.3 kg (5.1 lb). **Complete M72A3: 2.5 kg (5.5 lb). *'Firing mechanism': Percussion. *'Front sight': reticle graduated in 25 m range increments. *'Rear sight': peep sight adjusts automatically to temperature change. Rocket *'Caliber': 66 mm (2.6 in) *'Length': 508 mm (20 in) *'Weight': 1.8 kg (4 lb) *'Muzzle velocity': 145 m/s (475 ft/s) *'Minimum range (combat)': 10 m (33 ft) *'Minimum arming range': 10 m (33 ft) *'Maximum range': 1,000 m (3,300 ft) *'Penetration': 250 mm (10 inches) Maximum effective ranges *'Stationary target': 200 m (220 yd) *'Moving target':165 m (180 yd) *Beyond these ranges there is less than a 50 % chance of hitting the target. References External links *FAS *Gary's U.S. Infantry Weapons Reference Guide *Article on the reintroduction of the LAW in Iraq by the USMC *Canadian Military Page On the M72 *Patent for sights of M 72 Patented by Paul V. Choate of Milton, MA. *Patented by Paul V. Choate of Milton, MA. *1960s US Army M72 Training film Category:Weapons of the Vietnam War Category:Anti-communist forces weapons